initial version for key navigation

--there are some small issues but I think it can be fixed
fixes #65, dragging on Add Workarea with full animations

--a small bug from the new dragging architecture. This
occured when a window was dragged in Add Workarea button
and animations were in Full state.
fix focus on pop up

--when the plasmoid pops up then keynavigation must gain
focus
use same selection mechanism for hovering and keynavigation
preparing tasks filtering

--the model is in place so filtering is almost ready...
implemented windows filtering, small bug fixes in windows

--add functionality in counting windows in workareas
fixes #64, tested windows filtering with key backslash

--various small fixes in the tasks lists
Disable key navigation focus when a dialog is open

--or the user has a TextEdit focus
FIXED not showing windows in only one Desktop case
fixed closing a dialog by just clicking inside the window
fixed hiding previews in Everywhere panel when other Dialog uses them
BEAUTIFUL Feature: drag the window preview in calibration to set position
adds zoom in/out with Ctrl+Scroll wheel
restore functionality to restore wId in panel state
fixes #66, removed references that dont exist any more

--because tooltips mechanism changed to the default KDE
one, some dirt from the previous mechanism had remained...